This procedure provides general rules and specifications from the Service for paper and computer-generated substitutes of the extensively revised January 2005 versions of Form 941, Employer’s Quarterly Federal Tax Return, and Schedule B (Form 941), Report of Tax Liability for Semiweekly Schedule Depositors. Rev. Proc. 2005-21 will be reproduced as Publication 4436, General Rules and Specifications for Substitute Form 941 and Schedule B (Form 941).